Electronic devices and systems typically include a wide variety of components, sub-assemblies, and devices. For example, new electronic devices, such as mobile devices, may include memory, microprocessors, communication interfaces, transceivers, receivers, and display components. In addition, in many cases, these components, sub-assemblies, and devices will have differing power supply voltage and current requirements. For example, a display component configured to be in a sleep mode or turned off in order to conserve power may require a different power supply voltage level than when the display component is normally operating. Likewise, the power supply voltages and current requirements of the components, sub-assemblies, and devices may also vary depending upon the operational mode of the electronic devices and systems. These varying system power supply needs may be further complicated in the case where a battery is used to provide a system power source.
To meet the varying power supply needs of these diverse components, sub-assemblies, and devices, some electronic devices and systems rely upon power supply systems that use inductors to convert the voltage levels available from a system power source, such as a battery, to more desirable power supply voltages. In some cases, multiple inductors may be used. Other power supply systems may employ large numbers of capacitors to transform an available voltage level from a system power source, such as a battery, to more desirable power supply voltages. In addition, as the number of capacitors and inductors increase, the power supply systems may need to employ increased numbers of power switch and complex switching techniques to convert the voltage levels of an available system power source to more desirable power supply voltages.
Also, in some cases, components, sub-assemblies, and devices of these electronic devices and systems may require highly accurate voltage levels in order to properly function. In some cases where the system power source is provided by a battery, power supply systems that employ large numbers of capacitors or multiple inductors to transform a voltage level from an available system power source to a highly accurate voltage level may consume substantial amounts of energy, require substantially increased silicon areas or module areas, and be economically expensive.
Accordingly, there is a need to develop more efficient power management systems that may be reconfigured to provide a desired output voltage to each of the components, sub-assemblies, and devices of electronic devices and systems based upon the operational mode of the electronic devices and systems. In addition, there is also a need to develop power management systems that substantially reduce or eliminate the need for inductors and large numbers of capacitors to transform an available voltage level from a system power source, such as a battery, to more desirable power supply voltages. There is also a need to develop efficient power management systems that can flexibly provide highly accurate voltage levels that are substantially insensitive to a change in voltage level provided by a system power source, such as a battery.